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08:44
Assembly and Characterization of Polyelectrolyte Complex Micelles
Published on: March 2, 2020
Nanostructure of complexes between cationic lipids and an oppositely charged polyelectrolyte
Sharon Golan1, Yeshayahu Talmon
1Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Langmuir : the ACS Journal of Surfaces and Colloids
|January 5, 2012
Summary
Complexes of cationic lipids with poly(acrylic acid) (PAA) form onion-like nanostructures, similar to those seen with DNA and oligonucleotides. This suggests a universal packing phenomenon in polyelectrolyte-liposome systems.
Area of Science:
- Colloid Science
- Materials Science
- Biophysics
Background:
- Polyelectrolyte and oppositely charged lipid complexes are crucial in industry and medicine, particularly for gene therapy.
- Understanding their morphology is key to optimizing applications like drug and gene delivery.
Purpose of the Study:
- To investigate the morphology of complexes formed between cationic lipids (DOTAP, BFDMA) and the polyelectrolyte sodium poly(acrylic acid) (PAA).
- To compare this morphology with known lipoplexes formed by these lipids with nucleic acids.
- To identify universal packing phenomena in polyelectrolyte-liposome systems.
Main Methods:
- Direct-imaging cryogenic-temperature transmission electron microscopy (cryo-TEM) for detailed structural analysis.
- Dynamic light scattering (DLS) to determine particle size and distribution.
- Zeta (ζ)-potential measurements to assess surface charge characteristics.
Main Results:
- Both DOTAP/PAA and BFDMA/PAA complexes formed onion-like multilamellar nanostructures.
- The observed morphology was similar to that of lipoplexes formed by the same lipids with DNA or oligonucleotides.
- These structures formed at equivalent lipid/polyelectrolyte charge ratios.
Conclusions:
- The onion-like packing is a common and energetically favorable structure for various polyelectrolyte-liposome systems.
- This finding has implications for the design of delivery systems for nucleic acids and other charged molecules.
- The study highlights a universal packing principle in lipid-polyelectrolyte complex formation.
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